Available with 3D Analyst license.
A set of geoprocessing tools for editing existing terrains is available in the 3D Analyst toolbox. To ensure the toolbox is available, make sure 3D Analyst is installed and have it enabled via the Customize > Extensions dialog box.
In ArcToolbox, locate the 3D Analyst toolset, expand the Data Management toolset, then expand the Terrain Dataset toolset. The image below depicts the nine tools located in the Terrain Dataset toolset that can be used to edit terrain datasets.
Tools used to modify an existing terrain dataset
Adds one or more feature classes to a terrain dataset.
Adds one or more pyramid levels to an existing terrain dataset.
Appends points to a point feature referenced by a terrain dataset.
Performs tasks required for analyzing and displaying a terrain dataset.
Changes the reference scale associated with a terrain pyramid level.
Changes the pyramid levels at which a feature class will be enforced for a given terrain dataset.
Creates a new terrain dataset.
Deletes points within a specified area of interest from one or more features that participate in a terrain dataset.
Removes reference to a feature class participating in a terrain dataset.
Removes a pyramid level from a terrain dataset.
Replaces points referenced by a terrain dataset with points from a specified feature class.
Geoprocessing tools can edit properties of a terrain as well as embedded multipoint feature classes. Editable properties include pyramid definitions and information about participating feature classes. Changes other than those specifically associated with pyramid reference scales require a rebuild of the terrain. You can make multiple edits followed by one call to Build Terrain. This is more efficient than performing a build after every edit operation.